The development of immune and inflammatory responses requires the balanced activation of both humoral and cellular pathways. These pathways are regulated by the concerted effects of specific mediators such as cytokines and hormones which mobilize and coordinate localized processes including tissue invasion and antigen-specific responses. More specifically, during inflammation, cytokines attract additional immune cells to the site of infection, increase the expression of antigen presentation molecules and enhance the activation of B- and T-cells.
Macrophage migration inhibitory factor (also called MIF, GIF and GLIF) was the first T-cell derived soluble cytokine to be discovered in guinea pigs where it was shown to inhibit macrophage migration during the inflammatory response (Bloom and Bennett, Science, 1966, 153, 80-82). Since then, Weiser et al. have isolated the human macrophage migration inhibitory factor (Weiser et al., Proc. Natl. Acad. Sci. U. S. A., 1989, 86, 7522-7526) and the gene has been localized to chromosome 22q11 (Paralkar and Wistow, Genomics, 1994, 19, 48-51). The nucleotide and protein sequences of human macrophage migration inhibitory factor are furthermore disclosed in the PCT publication WO 90/11301 and U.S. Pat. No. 5,656,737 (Clark and Weiser, 1990) and (Wistow, 1997). Methods to isolate macrophage migration inhibitory factor from the ocular lens are disclosed in U.S. Pat. No. 5,328,990 (Wistow, 1994).
Macrophage migration inhibitory factor has been characterized as an anterior pituitary-derived hormone that potentiates lethal endotoxemia (Bucala, Immunol. Lett., 1994, 43, 23-26; Bucala, Circ. Shock, 1994, 44, 35-39), a factor which can override glucocorticoid-mediated suppression of inflammatory and immune responses (Calandra and Bucala, Crit. Rev. Immunol., 1997, 17, 77-88; Calandra and Bucala, J. Inflamm., 1995, 47, 39-51), and as an activator of T-cells after mitogenic or antigenic stimuli (Bacher et al., Proc. Natl. Acad. Sci. U. S. A., 1996, 93, 7849-7854).
This cytokine has been shown to have multiple roles within the confines of regulating the immune response as well as being associated with cell growth and differentiation during wound repair and carcinogenesis. Expression has been shown to be elevated in prostate adenocarcinomas (Arcuri et al., Prostate, 1999, 39, 159-165; Meyer-Siegler and Hudson, Urology, 1996, 48, 448-452), colon carcinomas of the mouse (Takahashi et al., Mol. Med., 1998, 4, 707-714), lipopolysacharide-induced HL60 cells (a leukemia cell line) (Nishihira et al., Biochem. Mol. Biol. Int., 1996, 40, 861-869), and upon treatment with ultraviolet radiation (Shimizu et al., J. Invest. Dermatol., 1999, 112, 210-215). The pharmacological modulation of MIF activity and/or expression may therefore be an appropriate point of therapeutic intervention in pathological conditions.
More recently, it has been demonstrated that expression is elevated in human first-trimester trophoblasts and is induced by human chorionic gonadotropin suggesting a role in embryo implantation and pregnancy (Arcuri et al., Biol. Reprod., 1999, 60, 1299-1303; Wada et al., Hum. Reprod., 1999, 14, 395-399). Disclosed in the PCT publication WO 96/09389 are methods to express and purify the human protein using a vector system in E. coli (Mozetic Francky and Francky, 1996).
The protein has been detected in the synovia of patients with rheumatoid arthritis (Onodera et al., Cytokine, 1999, 11, 163-167) and uveitis (Kitaichi et al., Invest. Ophthalmol. Vis. Sci., 1999, 40, 247-250) and its expression at sites of inflammation and from macrophages suggests a role for the mediator in regulating the function of macrophages in host defense (Calandra et al., J. Exp. Med., 1994, 179, 1895-1902). Activity of macrophage migration inhibitory factor has also been found to correlate well with delayed hypersensitivity and cellular immunity in humans (Bernhagen et al., J. Exp. Med., 1996, 183, 277-282; David, Proc. Natl. Acad. Sci. U. S. A., 1966, 56, 72-77). The protein has also been implicated in neural function and development in rodents (Bacher et al., Mol. Med., 1998, 4, 217-230; Matsunaga et al., J. Biol. Chem., 1999, 274, 3268-3271; Nishio et al., Biochim. Biophys. Acta., 1999, 1453, 74-82; Suzuki et al., Brain Res., 1999, 816, 457-462).
Currently, there are no known therapeutic agents which effectively inhibit the synthesis of macrophage migration inhibitory factor.
To date, investigative strategies aimed at modulating macrophage migration inhibitory factor function have involved the use of antibodies (Kobayashi et al., Hepatology, 1999, 29, 1752-1759), antisense expression vectors (Takahashi et al., Microbiol. Immunol., 1999, 43, 61-67; Waeber et al., Proc. Natl. Acad. Sci. U. S. A., 1997, 94, 4782-4787) and gene knock-outs in mice (Bozza et al., J. Exp. Med., 1999, 189, 341-346).
Disclosed in the PCT publications WO 98/17314 and WO 97/29635 are an assay to identify compounds that inhibit macrophage migration inhibitory factor activity and methods of preventing or treating disease by administering a therapeutic amount of a macrophage migration inhibitory factor antagonist agent whereby the agent is a monoclonal antibody, respectively (Bucala et al., 1997; Bucala and Chesney, 1998). The PCT publication, WO 96/15242 describes methods for inhibiting macrophage migration inhibitory factor in the mouse through the use of inhibitory nucleic acid molecules that hybridize to the initiation start site or to intron/exon borders (Wistow and Paralkar, 1996).
However, these strategies are untested as therapeutic protocols and consequently, there remains a long felt need for additional agents capable of effectively inhibiting macrophage migration inhibitory factor function.
Antisense technology is emerging as an effective means for reducing the expression of specific gene products and may therefore prove to be uniquely useful in a number of therapeutic, diagnostic, and research applications for the modulation of macrophage migration inhibitory factor expression.
The present invention provides compositions and methods for modulating macrophage migration inhibitory factor expression.